Patent · US Expired

Laser doppler velocimeter

US5587785A · kind A · utility

58Cited by
1References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 21, 1995
Grant dateDec 24, 1996
Priority date
Expiry dateMar 21, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02A90/10
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A laser Doppler velocimeter in which laser light whose frequency changes continuously at least for a fixed time duration is branched into at least two beams, and the at least two branched beams are respectively transmitted by at least one pair of optical fibers having an optical path difference therebetween, and are focused onto a region to be measured by at least one focusing device. The scattered light of the laser beams focused in the region to be measured are received by a light-receiving device via at least one incident device. At least one Doppler shift frequency in the region to be measured is calculated on the basis of the frequency of a signal of the scattered light received by the light-receiving device, the optical path difference, and a rate of change of the frequency of the laser light. The flow velocity and the direction of the flow velocity are calculated from the calculated Doppler shift frequency.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.